Back-and-forth cable systems are typically used for the practice of wakeboarding. They generally include two towers, a motor, a running cable extending between the towers and a carrier connected to the cable, for towing or pulling a boarder over a water area. In opposition to cableway systems, which enable several boarders to ride at the same time, and where the cable forms a loop running in a single direction, back-and-forth cable system are generally used for pulling one boarder at a time, the cable changing direction at the end of each course, in order for the carrier to move back-and-forth between the two towers.
A problem with existing systems is the difficulty to manage problems related to the cable, such as slippage of the cable over the pulleys, stretching of the cable, and especially lateral stretching, inadequate tensioning, etc. These problems make it difficult to precisely locate the carrier over a given course between the towers. Being able to locate the carrier precisely over the course is required for establishing the turning points, that is, the limit positions at which the carrier will change direction.
Slippage and lateral stretching of the cable is not an issue in cableway systems since such systems do not need determine precisely the position of the carrier: the carrier is moved continuously in the same direction and the rotation of the shaft of the motor is not stopped and inverted when in operation, such as required with back-and-forth system.
Some of the existing back-and-forth systems use motor encoders in order to determine the location of the carrier between the towers; however, an encoder cannot take account of slippage or stretching of the cable. The cable of a back-and-forth system can be suddenly tensioned and pulled away from their linear path since wakeboarders usually slalom and zigzag over the water surface, or jump over platforms and obstacles placed along the course, thereby stretching the cable laterally.
Another drawback of existing back-and-forth cable systems is the difficulty to easily and securely control their operation. The motor is generally controlled by means of a potentiometer which must be turned manually in order to vary the speed of the motor. Since the control is done manually, the acceleration of the carrier, the cruising speed and the position of the turning points are not steady or repeatable throughout a wakeboarding session, which is not ideal.
Another drawback of most existing back-and-forth cable system is the necessity to have access to an industrial 460V power line in order to power the system. The few existing systems which can be used with a 220V power line require cumbersome transformer or transducer for converting the single phase 220V line to a three-phase line.
In light of the above, there is a need for a control system and for a method of operating a back-and-forth cable system which are secure for both the rider and the operator. There is also a need for an automated back and forth cable system which provides a smooth, secure and predictable ride for the boarders.